class_docstr: Test the CVScores visualizer
docstr: Assert that fit returns self and creates expected properties
docstr_tok: ["Assert","that","fit","returns","self","and","creates","expected","properties"]
code: def test_fit(self, mock_draw):
      """
      Assert that fit returns self and creates expected properties
      """
      X, y = self.classification
  
      params = ("cv_scores_", "cv_scores_mean_")
  
      oz = CVScores(SVC())
  
      for param in params:
          assert not hasattr(oz, param)
  
      assert oz.fit(X, y) is oz
      mock_draw.assert_called_once()
  
      for param in params:
          assert hasattr(oz, param)
  
imports: import pytest
  import numpy.testing
  from unittest.mock import patch
  from tests.base import VisualTestCase
  from sklearn.svm import SVC
  from sklearn.naive_bayes import BernoulliNB
  from sklearn.tree import DecisionTreeRegressor
  from sklearn.preprocessing import OneHotEncoder, MinMaxScaler
  from sklearn.neighbors import KNeighborsClassifier
  from sklearn.linear_model import RidgeCV, LogisticRegressionCV
  from sklearn.model_selection import ShuffleSplit, StratifiedKFold
  from sklearn.pipeline import Pipeline
  from yellowbrick.datasets import load_mushroom
  from yellowbrick.model_selection.cross_validation import *
label_desc: Use image node_id 1 for calling the TestCrossValidation obj's underlying member method code with example usage: obj.test_fit(mock_draw) without return types